Ignition apparatus



Sept. 26, 1933.

J. T. FITZSIMMONS 7 1,928,222

IGNITION APPARATUS Original- Filed Oct. 2. 1931 Patented Sept. 26, 1933UNITED STAT IGNITION APPARATUS John T. Fitzsimmons, Anderson, IntL,assignor to Delco-Remy Corporation, Anderson, Ind., a corporation ofDelaware Application October 2, 1931, Serial No. Renewed July 2'1, 19328 Claims. (Cl. 123-148) 10 of the engine. When providing such a unit fora four-cycle internal combustion engine, the shaft of said unit isdriven preferably by the valve cam shaft of the engine at a speed ratioof one to one. Since the valve cam shaft of the engine operates 5 atone-half engine speed in a four-cycle internal combustion engine, theshaft of the ignition unit will rotate once during each two revolutions,or during one cycle of operation of the four-cycle internal combustionengine. Similarly, if the ignition unit is to be applied to a two-cycleinternal combustion engine, the unit is driven directly by the enginecrank shaft. Hence, the shaft of said ignition unit will rotate onceduring each revolutionof the crank shaft of the two cycle engine andhence during each cycle of operation thereof. j n In some instances itmay be advantageous to drive the shaft of the ignition unit at a'speedless than the cycle speed of the engine, for example, less than one-halfengine speed where applied to a four-cycle engine, or less thanenginespeed when applied to a two-cycle engine. It'is one of the objects ofthe present invention to provide an ignition timer and distributor unitoperated by a shaft which is driven at one-half cycle speed, forexample, one-fourth engine speed where applied to a four-cycle internalcombustion engine, 'or one-half engine speed where applied to atwo-cycle engine. 1

Further objects and advantages of the present invention will be apparentfrom the following description, reference being had to the accompanyingdrawing. wherein a preferred embodiment of one form f thepresentinvention is clearly shown.

The figure of the drawing is a wiring diagram illustrating a form of theinvention. Referring to the wiring diagram, designates 0 unit,saidj'shaft being driven by the engine (not 7 engine.

the shaft of the ignitiontimer and distributor cuit. interruptercomprising a pair of contacts 22 and 23, the former being grounded at 24and the latter being carried" by a metal lever 25 which is insulatinglysupported by a pivot 26. The lever 25 carriesa cam rubbing block 2'7 00-operating withcam 21. Leaf spring conductor 28 conducts current from theterminal 29 to the lever 25 and operates to urge-the contact 23 towardthe contact 22 and. the rubbing block 27 toward the cam 21.

The terminal 29 is connected with condenser 30 bywire 31 with anignition coil primary winding 32 which is connected with a switch 33with a battery 34 grounded at 35. An ignition coil secondary winding 36is grounded upon the battery through the switch 33 and is connected withthe central contact 37 of the ignition distributor. The contact 37engages the central part of a distributor rotor driven by the shaft 20.The rotor 38 is provided with diametrically opposite segments 39 and 40,each of which is adapted to distribute sparking impulses to either oftwo distributor posts or terminals 41, 42 connected by wires 43 and 44respectively, with spark plugs 45 and 46. 8O

1 The disclosed embodiment of the present inventionis constructedand'arranged for providing sparking impulses for a two cylinder Thetimer and distributor unit is constructed so as to rotate'in a clockwisedirection, asindicated by arrows 47 and 48; Since the shaft 20 rotatesat one-half cycle speed during each cycle of operation of the engine,the shaft 20 will turn one-half a revolution. Therefore, the four-lobecam 21 will cooperate with the circuit interrupter to separate thecontacts 22 and 23 twice during onehalf revolution of the shaft 20.

Each time the contacts 22, 23 are separated one of the segments of therotor 38 will be adjacent one of the posts of the distributor. Forexample, at one instant of separation of contacts 22, 23 the segment 40will be adjacent the distributor post 41 and at thenext instant ofseparation of contacts 22, 23 the segment 40 will be adjacent thedistributor post 42. Thus the two sparking impulses required fortheoperation of the twocylinder engine are generated and distributedconsequent to the one-whalf turn of the timer distributor drivingshaft20. During the next cycle of operation of the engine, the'shaft 20completes the other half turn of its rotary movement and during thisother half turn the segment 40 is inactive, but the'segment 39 isoperative to distribute sparking impulses successively to the posts- 41and 42.

It is apparent that the present invention may be applied to theconstruction of ignition timer and distributor units for engines havingany number of cylinders. For example, if the engine has three cylinders,the cam 2l will be provided with six lobes so; that three sparkingimpulses will be created during each half turn of the shaft 20. Thedistributor will be provided with three distributor posts with whichcooperates a seg ment similar to the segment 38, having diametricallyopposite distributing segments39 and,

40. The distributor posts will be arranged sixty degrees apart, insteadof ninety degrees gas in the disclosed form for a two-cylinder engine;Likewise, an ignition timer unit embodying the present invention andconstructed. and arranged for a four-cylinder engine will have eightcami' lobes and four distributor posts arrangedon. one. side of thedistributor head and spacedforty-five' degrees apart. l It is,therefore,,apparent that any ignition timer and distributor unitembodying the present invention will require its cam 21 to'have twiceasmany lobes as there are engine cylindersto be fired during each.enginepycle; andv that the,

distributor head will be provided with as many distributor posts asthere are engine cylinders and that these distributor posts will be,located in an arcuate row and spaced apart at anflangle equal to onehundredeighty degrees divided by the number of enginecylinders. In. eachcase, the distributor rotorrequired to cooperate with such distributorheads will, be one, having two ,diametricall y opposite" distributingsegments,

I N circularly arranged posts edual' in number to the explosion periodsduring an engine cycle.

The circularly-arranged posts are connected respectively withenginesparkgaps r The'reis a distributor rotor connected with the center te'r;

minal, and havingjt (a plurality of) .equiang'ularly spaced branches or.arms movable past said posts, said posts and ,arms being, so located andarranged .that, during one engine cycle, one arm serves all of the postsand that, during the next succeeding engine pycle, another arm servesall of theposts, and so. on until all of the arms have served,, Theangular spacing of the. circularly arranged posts is 360+R+NQ rotor isrotated by the engine at the rate of revolutions during each enginecycle. They inductirm generating means is controlled by circuitinterrupter means comprising B circuit breakers operated by acam havingM V I B lobes and operated by the engine at the rate of o L Rvrevolutions during an engine,,cycle,, B being so chosen that thequotient will be, aninteger. The following tabulation shows how thepresent inengines jhaving N explosion periods duringan envention can beapplied to engines having different numbers of cylinders, R alsovarying:

L, llllmbelNq earn Explosion Ratio of Angular b No. of periods rotorspeed spacing of Bznumber (break rotor during to engine spark gap ersbranches each encycle speed posts:

R ginecycle i 3 60 N R NR 2 s: a Q 6 QIIAIIAlIQIIi-lll 5 e e e e e 2 2/z 4 2 l 2 3 V2 60 6 3 2 4 /2 45 8 4 2' 5 /2 36 10 5 2 6 V2 30 12 6 90 28 a 22V; 16 8 4 3 2 A 60 6 3 2 3 3 40 9 3 3 4 30 12 e 4 3 5 A; 24 15 5 33 6 /{1 2O 18 9 6 3 8 /s 15 24 12 8 6,

4 2' 34 r 45- s 4 2 .4 3 M 3O 12 6 3 4 4 /4 22% 16 8 4 4 5 V4 18 20 10 54 4 0' M 15 24 12' 0 4 8 5/1 11 /4 32 16 s 5 2 A 36 10 5 3 /3 24 15 5 45 5 18 20 5 5 /5 14.4 25 5 6 ,4 I 12 30 5 8 /5 9 4O While the form ofembodiment of the present invention as herein disclosed, constitutes apreferred'form, it is to be understood that other forms might beadopted, all coming within the scope of the claims which followj What isclaimed is as follows:

1. Ignition apparatus for, internal combustion engines comprising, incombination, an ignition timer including a circuit breaker for theprimary circuit and a cam for operating the circuit breaker whoselobesnumber twice the number of engine cylinders, a distributor for thesecondary circuit comprising a head: carrying distributor postswhose'angular spacing equals 180 dividedby the number of enginecylinders, and a double-end r0 tor cooperating with said posts, saidrotor having diametrically opposite distributing arms, and a shaftdriving the cam and rotor and operated by the engine at one-half enginecycle speed.

2. Ignition apparatus for internal combustion engines 'cornprisingincombination, an ignition timer including a circuit breaker for theprimary circuit and a cam for operating the circuit breaker whose lobesnumber twice the number of engine cylinders, a distributor for thesecondary circuit conprising a head' carrying distributor posts, and adouble end rotor cooperating with said posts, saidrotorhavingdiametrically opposite distributing arms, and a shaft driving-thecam-and rotor and operated by the engine at one-halI-en gine cyclespeed.

, 3. Ignition apparatus forinternal combustion engines comprising, incombination, an ignition timerincluding a circuit breaker ,for theprimary circuit and a cam for operating the circuit breaker said camhaving lobes numbering twice the number of engine cylinders, and enginedriven shaft driving the cam at one-half engine cycle speed, and adistributor for the secondary circuit 14 including a head carryingdistributor posts and a rotor driven by said shaft at timer cam speed;

4. Ignition apparatus for internal combustion gine cycle comprising, incombination, a distributor head having a center terminal and Ncircularly arranged posts connected respectively with engine spark gapsand a distributing rotor connected with the center terminal and having R(a revolution during each engine cycle, and means for causing a sparkingimpulse to be delivered to the center terminal each time a rotor arm isadjacent a post.

5. Ignition apparatus for internal combustion engines having N explosionperiods during an engine cycle comprising, in combination, a distributorhead having a center terminal and N circularly arranged posts connectedrespectively with engine spark gaps and a distributing rotor connectedwith the center terminal and having R (a plurality of) branches or armsspaced 360/R degrees and movable past said posts, said posts and armsbeing equiangularly spaced 360/NR degrees so that, during one enginecycle, one of the arms serves all of the posts and that, during the nextsucceeding cycle, another of the arms serves all of the posts, enginedriven means for turning the rotor at the rate of revolution during eachengine cycle, induction generating means connected with the centerterminal and a circuit interrupting means comprising B circuit breakersoperated by a cam having cam lobes and operated by the engine at therate of revolution during each engine cycle, B being a number such thatthe quotient N X B B will be an integer.

6. Ignition apparatus for internal combustion engines having 2 explosionperiods during an en gine cycle comprising, in combination, a distributor head having a center terminal and 2 circularly arranged postsconnected respectively with engine spark gaps and a rotor connected withthe. center terminal and having 2 rotor branches or arms, said posts andarms being so located and arranged that, during one engine cycle, onearm serves both posts and that, during the next succeeding cycle, theother arm serves both posts, engine driven means for turning the rotorat the rate of revolution during each engine cycle and means for causinga sparking impulse to be delivered to the center terminal each time arotor arm is adjacent a post.

7. Ignition apparatus for internal combustion engines having 2 explosionperiods during an engine cycle comprising, in combination, a distributorhead having a center terminal and 2 circularly arranged posts connectedrespectively with engine spark gaps and a rotor connected with thecenter terminal and having 2 rotor branches or arms, said posts and armsbeing so located and arranged that, during one engine cycle, one armserves both posts and that, during the next succeeding cycle, the otherarm serves both posts, engine driven means for turning the rotor at therate of /2 revolution during each engine cycle, induction generatingmeans connected with the center terminal and a circuit interruptingmeans comprising B circuit breakers operated by a cam having cam lobesand operated by the engine at the rate of revolution during each enginecycle, B being equal to 1, 2 or 4.

8. Ignition apparatus for internal combustion engines having N explosionperiods during an engine cycle comprising, in combination, a distributorhead having a center terminal and N circularly arranged posts connectedrespectively with engine spark gaps and a rotor connected with thecenter terminal and having R distributing branches or arms movable pastsaid posts, said posts and arms being so located and arranged as tooperate alternately to serve all of the posts, means drivenby the enginefor turning the rotor at the rate of revolution during each enginecycle, and means for causing a sparking impulse to be delivered to thecenter terminal each time a rotor arm is adjacent a post.

' JOHN T. FITZSIMMONS

